op: add package op for operations

Extract operation types from package ui into package op.

Signed-off-by: Elias Naur <mail@eliasnaur.com>

app/internal/gpu/gpu.go

@@ -12,11 +12,11 @@ import (
 	"strings"
 	"time"
 
-	"gioui.org/ui"
 	"gioui.org/app/internal/gl"
 	"gioui.org/f32"
 	"gioui.org/internal/opconst"
 	"gioui.org/internal/ops"
+	"gioui.org/op"
 	"gioui.org/paint"
 	"golang.org/x/image/draw"
 )
@@ -74,7 +74,7 @@ type drawOps struct {
 
 type drawState struct {
 	clip  f32.Rectangle
-	t     ui.TransformOp
+	t     op.TransformOp
 	cpath *pathOp
 	rect  bool
 	z     int
@@ -398,7 +398,7 @@ func (g *GPU) Refresh() {
 	g.setErr(<-g.refreshErr)
 }
 
-func (g *GPU) Draw(profile bool, viewport image.Point, root *ui.Ops) {
+func (g *GPU) Draw(profile bool, viewport image.Point, root *op.Ops) {
 	if g.err != nil {
 		return
 	}
@@ -678,7 +678,7 @@ func (d *drawOps) reset(cache *resourceCache, viewport image.Point) {
 	d.pathOpCache = d.pathOpCache[:0]
 }
 
-func (d *drawOps) collect(cache *resourceCache, root *ui.Ops, viewport image.Point) {
+func (d *drawOps) collect(cache *resourceCache, root *op.Ops, viewport image.Point) {
 	d.reset(cache, viewport)
 	clip := f32.Rectangle{
 		Max: f32.Point{X: float32(viewport.X), Y: float32(viewport.Y)},
@@ -704,8 +704,8 @@ loop:
 	for encOp, ok := r.Decode(); ok; encOp, ok = r.Decode() {
 		switch opconst.OpType(encOp.Data[0]) {
 		case opconst.TypeTransform:
-			op := ops.DecodeTransformOp(encOp.Data)
+			dop := ops.DecodeTransformOp(encOp.Data)
-			state.t = state.t.Multiply(ui.TransformOp(op))
+			state.t = state.t.Multiply(op.TransformOp(dop))
 		case opconst.TypeAux:
 			aux = encOp.Data[opconst.TypeAuxLen:]
 			auxKey = encOp.Key

app/internal/input/key.go

@@ -7,7 +7,7 @@ import (
 	"gioui.org/internal/ops"
 	"gioui.org/io/event"
 	"gioui.org/io/key"
-	"gioui.org/ui"
+	"gioui.org/op"
 )
 
 type TextInputState uint8
@@ -44,7 +44,7 @@ func (q *keyQueue) InputState() TextInputState {
 	return q.state
 }
 
-func (q *keyQueue) Frame(root *ui.Ops, events *handlerEvents) {
+func (q *keyQueue) Frame(root *op.Ops, events *handlerEvents) {
 	if q.handlers == nil {
 		q.handlers = make(map[event.Key]*keyHandler)
 	}

app/internal/input/pointer.go

@@ -11,7 +11,7 @@ import (
 	"gioui.org/internal/ops"
 	"gioui.org/io/event"
 	"gioui.org/io/pointer"
-	"gioui.org/ui"
+	"gioui.org/op"
 )
 
 type pointerQueue struct {
@@ -42,7 +42,7 @@ type pointerInfo struct {
 type pointerHandler struct {
 	area      int
 	active    bool
-	transform ui.TransformOp
+	transform op.TransformOp
 	wantsGrab bool
 }
 
@@ -52,7 +52,7 @@ type areaOp struct {
 }
 
 type areaNode struct {
-	trans ui.TransformOp
+	trans op.TransformOp
 	next  int
 	area  areaOp
 }
@@ -64,7 +64,7 @@ const (
 	areaEllipse
 )
 
-func (q *pointerQueue) collectHandlers(r *ops.Reader, events *handlerEvents, t ui.TransformOp, area, node int, pass bool) {
+func (q *pointerQueue) collectHandlers(r *ops.Reader, events *handlerEvents, t op.TransformOp, area, node int, pass bool) {
 	for encOp, ok := r.Decode(); ok; encOp, ok = r.Decode() {
 		switch opconst.OpType(encOp.Data[0]) {
 		case opconst.TypePush:
@@ -86,8 +86,8 @@ func (q *pointerQueue) collectHandlers(r *ops.Reader, events *handlerEvents, t u
 			})
 			node = len(q.hitTree) - 1
 		case opconst.TypeTransform:
-			op := ops.DecodeTransformOp(encOp.Data)
+			dop := ops.DecodeTransformOp(encOp.Data)
-			t = t.Multiply(ui.TransformOp(op))
+			t = t.Multiply(op.TransformOp(dop))
 		case opconst.TypePointerInput:
 			op := decodePointerInputOp(encOp.Data, encOp.Refs)
 			q.hitTree = append(q.hitTree, hitNode{
@@ -158,7 +158,7 @@ func (q *pointerQueue) init() {
 	}
 }
 
-func (q *pointerQueue) Frame(root *ui.Ops, events *handlerEvents) {
+func (q *pointerQueue) Frame(root *op.Ops, events *handlerEvents) {
 	q.init()
 	for _, h := range q.handlers {
 		// Reset handler.
@@ -167,7 +167,7 @@ func (q *pointerQueue) Frame(root *ui.Ops, events *handlerEvents) {
 	q.hitTree = q.hitTree[:0]
 	q.areas = q.areas[:0]
 	q.reader.Reset(root)
-	q.collectHandlers(&q.reader, events, ui.TransformOp{}, -1, -1, false)
+	q.collectHandlers(&q.reader, events, op.TransformOp{}, -1, -1, false)
 	for k, h := range q.handlers {
 		if !h.active {
 			q.dropHandler(k)

app/internal/input/router.go

@@ -12,7 +12,7 @@ import (
 	"gioui.org/io/key"
 	"gioui.org/io/pointer"
 	"gioui.org/io/profile"
-	"gioui.org/ui"
+	"gioui.org/op"
 )
 
 // Router is a Queue implementation that routes events from
@@ -53,7 +53,7 @@ func (q *Router) Events(k event.Key) []event.Event {
 	return events
 }
 
-func (q *Router) Frame(ops *ui.Ops) {
+func (q *Router) Frame(ops *op.Ops) {
 	q.handlers.Clear()
 	q.wakeup = false
 	q.profHandlers = q.profHandlers[:0]
@@ -160,12 +160,12 @@ func decodeProfileOp(d []byte, refs []interface{}) profile.Op {
 	}
 }
 
-func decodeInvalidateOp(d []byte) ui.InvalidateOp {
+func decodeInvalidateOp(d []byte) op.InvalidateOp {
 	bo := binary.LittleEndian
 	if opconst.OpType(d[0]) != opconst.TypeInvalidate {
 		panic("invalid op")
 	}
-	var o ui.InvalidateOp
+	var o op.InvalidateOp
 	if nanos := bo.Uint64(d[1:]); nanos > 0 {
 		o.At = time.Unix(0, int64(nanos))
 	}

app/window.go

@@ -12,6 +12,7 @@ import (
 	"gioui.org/app/internal/input"
 	"gioui.org/io/event"
 	"gioui.org/io/profile"
+	"gioui.org/op"
 	"gioui.org/ui"
 )
 
@@ -36,7 +37,7 @@ type Window struct {
 	in          chan event.Event
 	ack         chan struct{}
 	invalidates chan struct{}
-	frames      chan *ui.Ops
+	frames      chan *op.Ops
 
 	stage        Stage
 	animating    bool
@@ -99,7 +100,7 @@ func NewWindow(options ...WindowOption) *Window {
 		out:         make(chan event.Event),
 		ack:         make(chan struct{}),
 		invalidates: make(chan struct{}, 1),
-		frames:      make(chan *ui.Ops),
+		frames:      make(chan *op.Ops),
 	}
 	go w.run(opts)
 	return w
@@ -120,11 +121,11 @@ func (w *Window) Queue() *Queue {
 // window contents, input operations declare input handlers,
 // and so on. The supplied operations list completely replaces
 // the window state from previous calls.
-func (w *Window) Update(frame *ui.Ops) {
+func (w *Window) Update(frame *op.Ops) {
 	w.frames <- frame
 }
 
-func (w *Window) draw(size image.Point, frame *ui.Ops) {
+func (w *Window) draw(size image.Point, frame *op.Ops) {
 	var drawDur time.Duration
 	if !w.drawStart.IsZero() {
 		drawDur = time.Since(w.drawStart)
@@ -265,7 +266,7 @@ func (w *Window) run(opts *windowOptions) {
 				w.drawStart = time.Now()
 				w.hasNextFrame = false
 				w.out <- e
-				var frame *ui.Ops
+				var frame *op.Ops
 				// Wait for either a frame or the ack event,
 				// which meant that the client didn't draw.
 				select {

cmd/gogio/testdata/red.go

@@ -7,7 +7,6 @@ import (
 	"image/color"
 	"log"
 
-	"gioui.org/ui"
 	"gioui.org/app"
 	"gioui.org/f32"
 	"gioui.org/paint"
@@ -25,7 +24,7 @@ func main() {
 
 func loop(w *app.Window) error {
 	background := color.RGBA{255, 0, 0, 255}
-	ops := new(ui.Ops)
+	ops := new(op.Ops)
 	for {
 		e := <-w.Events()
 		switch e := e.(type) {

gesture/gesture.go

@@ -16,6 +16,7 @@ import (
 	"gioui.org/internal/fling"
 	"gioui.org/io/event"
 	"gioui.org/io/pointer"
+	"gioui.org/op"
 	"gioui.org/ui"
 )
 
@@ -95,7 +96,7 @@ const (
 var touchSlop = ui.Dp(3)
 
 // Add the handler to the operation list to receive click events.
-func (c *Click) Add(ops *ui.Ops) {
+func (c *Click) Add(ops *op.Ops) {
 	op := pointer.InputOp{Key: c}
 	op.Add(ops)
 }
@@ -140,11 +141,11 @@ func (c *Click) Events(q event.Queue) []ClickEvent {
 }
 
 // Add the handler to the operation list to receive scroll events.
-func (s *Scroll) Add(ops *ui.Ops) {
+func (s *Scroll) Add(ops *op.Ops) {
 	oph := pointer.InputOp{Key: s, Grab: s.grab}
 	oph.Add(ops)
 	if s.flinger.Active() {
-		ui.InvalidateOp{}.Add(ops)
+		op.InvalidateOp{}.Add(ops)
 	}
 }
 

internal/ops/ops.go

@@ -6,17 +6,17 @@ import (
 	"encoding/binary"
 	"math"
 
-	"gioui.org/ui"
 	"gioui.org/f32"
 	"gioui.org/internal/opconst"
+	"gioui.org/op"
 )
 
-func DecodeTransformOp(d []byte) ui.TransformOp {
+func DecodeTransformOp(d []byte) op.TransformOp {
 	bo := binary.LittleEndian
 	if opconst.OpType(d[0]) != opconst.TypeTransform {
 		panic("invalid op")
 	}
-	return ui.TransformOp{}.Offset(f32.Point{
+	return op.TransformOp{}.Offset(f32.Point{
 		X: math.Float32frombits(bo.Uint32(d[1:])),
 		Y: math.Float32frombits(bo.Uint32(d[5:])),
 	})

internal/ops/reader.go

@@ -5,15 +5,15 @@ package ops
 import (
 	"encoding/binary"
 
-	"gioui.org/ui"
 	"gioui.org/internal/opconst"
+	"gioui.org/op"
 )
 
 // Reader parses an ops list.
 type Reader struct {
 	pc    pc
 	stack []macro
-	ops   *ui.Ops
+	ops   *op.Ops
 }
 
 // EncodedOp represents an encoded op returned by
@@ -26,14 +26,14 @@ type EncodedOp struct {
 
 // Key is a unique key for a given op.
 type Key struct {
-	ops     *ui.Ops
+	ops     *op.Ops
 	pc      int
 	version int
 }
 
-// Shadow of ui.MacroOp.
+// Shadow of op.MacroOp.
 type macroOp struct {
-	ops     *ui.Ops
+	ops     *op.Ops
 	version int
 	pc      pc
 }
@@ -44,7 +44,7 @@ type pc struct {
 }
 
 type macro struct {
-	ops   *ui.Ops
+	ops   *op.Ops
 	retPC pc
 	endPC pc
 }
@@ -58,7 +58,7 @@ type opAux struct {
 }
 
 // Reset start reading from the op list.
-func (r *Reader) Reset(ops *ui.Ops) {
+func (r *Reader) Reset(ops *op.Ops) {
 	r.stack = r.stack[:0]
 	r.pc = pc{}
 	r.ops = ops
@@ -170,7 +170,7 @@ func (m *macroOp) decode(data []byte, refs []interface{}) {
 	refsIdx := int(int32(bo.Uint32(data[5:])))
 	version := int(int32(bo.Uint32(data[9:])))
 	*m = macroOp{
-		ops: refs[0].(*ui.Ops),
+		ops: refs[0].(*op.Ops),
 		pc: pc{
 			data: dataIdx,
 			refs: refsIdx,

io/event/event.go

@@ -23,7 +23,7 @@ The following example declares a handler ready for key input:
 
 	import gioui.org/io/key
 
-	ops := new(ui.Ops)
+	ops := new(op.Ops)
 	var h *Handler = ...
 	key.InputOp{Key: h}.Add(ops)
 

io/key/key.go

@@ -12,7 +12,7 @@ package key
 import (
 	"gioui.org/internal/opconst"
 	"gioui.org/io/event"
-	"gioui.org/ui"
+	"gioui.org/op"
 )
 
 // InputOp declares a handler ready for key events.
@@ -86,7 +86,7 @@ func (m Modifiers) Contain(m2 Modifiers) bool {
 	return m&m2 == m2
 }
 
-func (h InputOp) Add(o *ui.Ops) {
+func (h InputOp) Add(o *op.Ops) {
 	data := make([]byte, opconst.TypeKeyInputLen)
 	data[0] = byte(opconst.TypeKeyInput)
 	if h.Focus {
@@ -95,7 +95,7 @@ func (h InputOp) Add(o *ui.Ops) {
 	o.Write(data, h.Key)
 }
 
-func (h HideInputOp) Add(o *ui.Ops) {
+func (h HideInputOp) Add(o *op.Ops) {
 	data := make([]byte, opconst.TypeHideInputLen)
 	data[0] = byte(opconst.TypeHideInput)
 	o.Write(data)

io/pointer/doc.go

@@ -15,7 +15,7 @@ subsequent InputOp are active.
 
 For example, to set up a rectangular hit area:
 
-	var ops ui.Ops
+	var ops op.Ops
 	var h *Handler = ...
 
 	r := image.Rectangle{...}
@@ -33,8 +33,8 @@ with the most recent node.
 
 For example:
 
-	ops := new(ui.Ops)
+	ops := new(op.Ops)
-	var stack ui.StackOp
+	var stack op.StackOp
 	var h1, h2 *Handler
 
 	stack.Push(ops)

io/pointer/pointer.go

@@ -10,7 +10,7 @@ import (
 	"gioui.org/f32"
 	"gioui.org/internal/opconst"
 	"gioui.org/io/event"
-	"gioui.org/ui"
+	"gioui.org/op"
 )
 
 // Event is a pointer event.
@@ -33,7 +33,7 @@ type Event struct {
 	// outside it.
 	Hit bool
 	// Position is the position of the event, relative to
-	// the current transformation, as set by ui.TransformOp.
+	// the current transformation, as set by op.TransformOp.
 	Position f32.Point
 	// Scroll is the scroll amount, if any.
 	Scroll f32.Point
@@ -124,21 +124,21 @@ const (
 	areaEllipse
 )
 
-func (op RectAreaOp) Add(ops *ui.Ops) {
+func (op RectAreaOp) Add(ops *op.Ops) {
 	areaOp{
 		kind: areaRect,
 		rect: op.Rect,
 	}.add(ops)
 }
 
-func (op EllipseAreaOp) Add(ops *ui.Ops) {
+func (op EllipseAreaOp) Add(ops *op.Ops) {
 	areaOp{
 		kind: areaEllipse,
 		rect: op.Rect,
 	}.add(ops)
 }
 
-func (op areaOp) add(o *ui.Ops) {
+func (op areaOp) add(o *op.Ops) {
 	data := make([]byte, opconst.TypeAreaLen)
 	data[0] = byte(opconst.TypeArea)
 	data[1] = byte(op.kind)
@@ -150,7 +150,7 @@ func (op areaOp) add(o *ui.Ops) {
 	o.Write(data)
 }
 
-func (h InputOp) Add(o *ui.Ops) {
+func (h InputOp) Add(o *op.Ops) {
 	data := make([]byte, opconst.TypePointerInputLen)
 	data[0] = byte(opconst.TypePointerInput)
 	if h.Grab {
@@ -159,7 +159,7 @@ func (h InputOp) Add(o *ui.Ops) {
 	o.Write(data, h.Key)
 }
 
-func (op PassOp) Add(o *ui.Ops) {
+func (op PassOp) Add(o *op.Ops) {
 	data := make([]byte, opconst.TypePassLen)
 	data[0] = byte(opconst.TypePass)
 	if op.Pass {

io/profile/profile.go

@@ -7,7 +7,7 @@ package profile
 import (
 	"gioui.org/internal/opconst"
 	"gioui.org/io/event"
-	"gioui.org/ui"
+	"gioui.org/op"
 )
 
 // Op registers a handler for receiving
@@ -23,7 +23,7 @@ type Event struct {
 	Timings string
 }
 
-func (p Op) Add(o *ui.Ops) {
+func (p Op) Add(o *op.Ops) {
 	data := make([]byte, opconst.TypeProfileLen)
 	data[0] = byte(opconst.TypeProfile)
 	o.Write(data, p.Key)

layout/flex.go

@@ -6,7 +6,7 @@ import (
 	"image"
 
 	"gioui.org/f32"
-	"gioui.org/ui"
+	"gioui.org/op"
 )
 
 // Flex lays out child elements along an axis,
@@ -21,7 +21,7 @@ type Flex struct {
 	Alignment Alignment
 
 	ctx       *Context
-	macro     ui.MacroOp
+	macro     op.MacroOp
 	mode      flexMode
 	size      int
 	rigidSize int
@@ -33,7 +33,7 @@ type Flex struct {
 
 // FlexChild is the layout result of a call End.
 type FlexChild struct {
-	macro ui.MacroOp
+	macro op.MacroOp
 	dims  Dimensions
 }
 
@@ -189,9 +189,9 @@ func (f *Flex) Layout(children ...FlexChild) {
 				cross = f.maxBaseline - b
 			}
 		}
-		var stack ui.StackOp
+		var stack op.StackOp
 		stack.Push(f.ctx.Ops)
-		ui.TransformOp{}.Offset(toPointF(axisPoint(f.Axis, mainSize, cross))).Add(f.ctx.Ops)
+		op.TransformOp{}.Offset(toPointF(axisPoint(f.Axis, mainSize, cross))).Add(f.ctx.Ops)
 		child.macro.Add(f.ctx.Ops)
 		stack.Pop()
 		mainSize += axisMain(f.Axis, dims.Size)

layout/layout.go

@@ -6,6 +6,7 @@ import (
 	"image"
 
 	"gioui.org/io/event"
+	"gioui.org/op"
 	"gioui.org/ui"
 )
 
@@ -53,7 +54,7 @@ type Context struct {
 
 	ui.Config
 	event.Queue
-	*ui.Ops
+	*op.Ops
 }
 
 const (
@@ -97,7 +98,7 @@ func (c *Context) Reset(cfg ui.Config, cs Constraints) {
 	c.Dimensions = Dimensions{}
 	c.Config = cfg
 	if c.Ops == nil {
-		c.Ops = new(ui.Ops)
+		c.Ops = new(op.Ops)
 	}
 	c.Ops.Reset()
 }
@@ -157,9 +158,9 @@ func (in Inset) Layout(gtx *Context, w Widget) {
 	if mcs.Height.Max < mcs.Height.Min {
 		mcs.Height.Max = mcs.Height.Min
 	}
-	var stack ui.StackOp
+	var stack op.StackOp
 	stack.Push(gtx.Ops)
-	ui.TransformOp{}.Offset(toPointF(image.Point{X: left, Y: top})).Add(gtx.Ops)
+	op.TransformOp{}.Offset(toPointF(image.Point{X: left, Y: top})).Add(gtx.Ops)
 	dims := gtx.Layout(mcs, w)
 	stack.Pop()
 	gtx.Dimensions = Dimensions{
@@ -176,7 +177,7 @@ func UniformInset(v ui.Value) Inset {
 
 // Layout a widget.
 func (a Align) Layout(gtx *Context, w Widget) {
-	var macro ui.MacroOp
+	var macro op.MacroOp
 	macro.Record(gtx.Ops)
 	cs := gtx.Constraints
 	mcs := cs
@@ -204,9 +205,9 @@ func (a Align) Layout(gtx *Context, w Widget) {
 	case SW, S, SE:
 		p.Y = sz.Y - dims.Size.Y
 	}
-	var stack ui.StackOp
+	var stack op.StackOp
 	stack.Push(gtx.Ops)
-	ui.TransformOp{}.Offset(toPointF(p)).Add(gtx.Ops)
+	op.TransformOp{}.Offset(toPointF(p)).Add(gtx.Ops)
 	macro.Add(gtx.Ops)
 	stack.Pop()
 	gtx.Dimensions = Dimensions{

layout/list.go

@@ -7,13 +7,13 @@ import (
 
 	"gioui.org/gesture"
 	"gioui.org/io/pointer"
+	"gioui.org/op"
 	"gioui.org/paint"
-	"gioui.org/ui"
 )
 
 type scrollChild struct {
 	size  image.Point
-	macro ui.MacroOp
+	macro op.MacroOp
 }
 
 // List displays a subsection of a potentially infinitely
@@ -33,8 +33,8 @@ type List struct {
 	beforeEnd bool
 
 	ctx         *Context
-	macro       ui.MacroOp
+	macro       op.MacroOp
-	child       ui.MacroOp
+	child       op.MacroOp
 	scroll      gesture.Scroll
 	scrollDelta int
 
@@ -246,10 +246,10 @@ func (l *List) layout() Dimensions {
 			Min: axisPoint(l.Axis, min, -inf),
 			Max: axisPoint(l.Axis, max, inf),
 		}
-		var stack ui.StackOp
+		var stack op.StackOp
 		stack.Push(ops)
 		paint.RectClip(r).Add(ops)
-		ui.TransformOp{}.Offset(toPointF(axisPoint(l.Axis, pos, cross))).Add(ops)
+		op.TransformOp{}.Offset(toPointF(axisPoint(l.Axis, pos, cross))).Add(ops)
 		child.macro.Add(ops)
 		stack.Pop()
 		pos += childSize

layout/stack.go

@@ -5,7 +5,7 @@ package layout
 import (
 	"image"
 
-	"gioui.org/ui"
+	"gioui.org/op"
 )
 
 // Stack lays out child elements on top of each other,
@@ -15,7 +15,7 @@ type Stack struct {
 	// smaller than the available space.
 	Alignment Direction
 
-	macro       ui.MacroOp
+	macro       op.MacroOp
 	constrained bool
 	ctx         *Context
 	maxSZ       image.Point
@@ -24,7 +24,7 @@ type Stack struct {
 
 // StackChild is the layout result of a call to End.
 type StackChild struct {
-	macro ui.MacroOp
+	macro op.MacroOp
 	dims  Dimensions
 }
 
@@ -99,9 +99,9 @@ func (s *Stack) Layout(children ...StackChild) {
 		case SW, S, SE:
 			p.Y = s.maxSZ.Y - sz.Y
 		}
-		var stack ui.StackOp
+		var stack op.StackOp
 		stack.Push(s.ctx.Ops)
-		ui.TransformOp{}.Offset(toPointF(p)).Add(s.ctx.Ops)
+		op.TransformOp{}.Offset(toPointF(p)).Add(s.ctx.Ops)
 		ch.macro.Add(s.ctx.Ops)
 		stack.Pop()
 	}

measure/measure.go

@@ -10,10 +10,11 @@ import (
 	"unicode"
 	"unicode/utf8"
 
-	"gioui.org/ui"
 	"gioui.org/f32"
+	"gioui.org/op"
 	"gioui.org/paint"
 	"gioui.org/text"
+	"gioui.org/ui"
 	"golang.org/x/image/font"
 	"golang.org/x/image/font/sfnt"
 	"golang.org/x/image/math/fixed"
@@ -34,7 +35,7 @@ type cachedLayout struct {
 
 type cachedPath struct {
 	active bool
-	path   ui.MacroOp
+	path   op.MacroOp
 }
 
 type layoutKey struct {
@@ -128,7 +129,7 @@ func (f *Face) Layout(str string, opts text.LayoutOptions) *text.Layout {
 	return l
 }
 
-func (f *Face) Path(str text.String) ui.MacroOp {
+func (f *Face) Path(str text.String) op.MacroOp {
 	ppem := fixed.Int26_6(f.faces.config.Px(f.size) * 64)
 	pk := pathKey{
 		f:    f.font.Font,
@@ -234,14 +235,14 @@ func layoutText(ppem fixed.Int26_6, str string, f *opentype, opts text.LayoutOpt
 	return &text.Layout{Lines: lines}
 }
 
-func textPath(ppem fixed.Int26_6, f *opentype, str text.String) ui.MacroOp {
+func textPath(ppem fixed.Int26_6, f *opentype, str text.String) op.MacroOp {
 	var lastPos f32.Point
 	var builder paint.PathBuilder
-	ops := new(ui.Ops)
+	ops := new(op.Ops)
 	builder.Init(ops)
 	var x fixed.Int26_6
 	var advIdx int
-	var m ui.MacroOp
+	var m op.MacroOp
 	m.Record(ops)
 	for _, r := range str.String {
 		if !unicode.IsSpace(r) {

op/op.go

@@ -1,10 +1,67 @@
 // SPDX-License-Identifier: Unlicense OR MIT
 
-package ui
+/*
+
+Package op implements operations for updating a user interface.
+
+Gio programs use operations, or ops, for describing their user
+interfaces. There are operations for drawing, defining input
+handlers, changing window properties as well as operations for
+controlling the execution of other operations.
+
+Ops represents a list of operations. The most important use
+for an Ops list is to describe a complete user interface update
+to a ui/app.Window's Update method.
+
+Drawing a colored square:
+
+	import "gioui.org/ui"
+	import "gioui.org/app"
+	import "gioui.org/paint"
+
+	var w app.Window
+	ops := new(op.Ops)
+	...
+	ops.Reset()
+	paint.ColorOp{Color: ...}.Add(ops)
+	paint.PaintOp{Rect: ...}.Add(ops)
+	w.Update(ops)
+
+State
+
+An Ops list can be viewed as a very simple virtual machine: it has an implicit
+mutable state stack and execution flow can be controlled with macros.
+
+The StackOp saves the current state to the state stack and restores it later:
+
+	ops := new(op.Ops)
+	var stack op.StackOp
+	// Save the current state, in particular the transform.
+	stack.Push(ops)
+	// Apply a transform to subsequent operations.
+	op.TransformOp{}.Offset(...).Add(ops)
+	...
+	// Restore the previous transform.
+	stack.Pop()
+
+The MacroOp records a list of operations to be executed later:
+
+	ops := new(op.Ops)
+	var macro op.MacroOp
+	macro.Record()
+	// Record operations by adding them.
+	op.InvalidateOp{}.Add(ops)
+	...
+
+*/
+package op
 
 import (
 	"encoding/binary"
+	"math"
+	"time"
 
+	"gioui.org/f32"
 	"gioui.org/internal/opconst"
 )
 
@@ -45,6 +102,18 @@ type MacroOp struct {
 	pc        pc
 }
 
+// InvalidateOp requests a redraw at the given time. Use
+// the zero value to request an immediate redraw.
+type InvalidateOp struct {
+	At time.Time
+}
+
+// TransformOp applies a transform to the current transform.
+type TransformOp struct {
+	// TODO: general transformations.
+	offset f32.Point
+}
+
 type pc struct {
 	data int
 	refs int
@@ -208,3 +277,48 @@ func (m MacroOp) Add(o *Ops) {
 	bo.PutUint32(data[9:], uint32(m.version))
 	o.Write(data, m.ops)
 }
+
+func (r InvalidateOp) Add(o *Ops) {
+	data := make([]byte, opconst.TypeRedrawLen)
+	data[0] = byte(opconst.TypeInvalidate)
+	bo := binary.LittleEndian
+	// UnixNano cannot represent the zero time.
+	if t := r.At; !t.IsZero() {
+		nanos := t.UnixNano()
+		if nanos > 0 {
+			bo.PutUint64(data[1:], uint64(nanos))
+		}
+	}
+	o.Write(data)
+}
+
+// Offset the transformation.
+func (t TransformOp) Offset(o f32.Point) TransformOp {
+	return t.Multiply(TransformOp{o})
+}
+
+// Invert the transformation.
+func (t TransformOp) Invert() TransformOp {
+	return TransformOp{offset: t.offset.Mul(-1)}
+}
+
+// Transform a point.
+func (t TransformOp) Transform(p f32.Point) f32.Point {
+	return p.Add(t.offset)
+}
+
+// Multiply by a transformation.
+func (t TransformOp) Multiply(t2 TransformOp) TransformOp {
+	return TransformOp{
+		offset: t.offset.Add(t2.offset),
+	}
+}
+
+func (t TransformOp) Add(o *Ops) {
+	data := make([]byte, opconst.TypeTransformLen)
+	data[0] = byte(opconst.TypeTransform)
+	bo := binary.LittleEndian
+	bo.PutUint32(data[1:], math.Float32bits(t.offset.X))
+	bo.PutUint32(data[5:], math.Float32bits(t.offset.Y))
+	o.Write(data)
+}

paint/paint.go

@@ -8,9 +8,9 @@ import (
 	"image/color"
 	"math"
 
-	"gioui.org/ui"
 	"gioui.org/f32"
 	"gioui.org/internal/opconst"
+	"gioui.org/op"
 )
 
 // ImageOp sets the material to a section of an
@@ -33,7 +33,7 @@ type PaintOp struct {
 	Rect f32.Rectangle
 }
 
-func (i ImageOp) Add(o *ui.Ops) {
+func (i ImageOp) Add(o *op.Ops) {
 	data := make([]byte, opconst.TypeImageLen)
 	data[0] = byte(opconst.TypeImage)
 	bo := binary.LittleEndian
@@ -44,7 +44,7 @@ func (i ImageOp) Add(o *ui.Ops) {
 	o.Write(data, i.Src)
 }
 
-func (c ColorOp) Add(o *ui.Ops) {
+func (c ColorOp) Add(o *op.Ops) {
 	data := make([]byte, opconst.TypeColorLen)
 	data[0] = byte(opconst.TypeColor)
 	data[1] = c.Color.R
@@ -54,7 +54,7 @@ func (c ColorOp) Add(o *ui.Ops) {
 	o.Write(data)
 }
 
-func (d PaintOp) Add(o *ui.Ops) {
+func (d PaintOp) Add(o *op.Ops) {
 	data := make([]byte, opconst.TypePaintLen)
 	data[0] = byte(opconst.TypePaint)
 	bo := binary.LittleEndian

paint/path.go

@@ -7,10 +7,10 @@ import (
 	"math"
 	"unsafe"
 
-	"gioui.org/ui"
 	"gioui.org/f32"
 	"gioui.org/internal/opconst"
 	"gioui.org/internal/path"
+	"gioui.org/op"
 )
 
 // PathBuilder builds and adds a general ClipOp clip path
@@ -19,7 +19,7 @@ import (
 // dynamic paths; path data is stored directly in the Ops
 // list supplied to Init.
 type PathBuilder struct {
-	ops       *ui.Ops
+	ops       *op.Ops
 	firstVert int
 	nverts    int
 	maxy      float32
@@ -33,7 +33,7 @@ type ClipOp struct {
 	bounds f32.Rectangle
 }
 
-func (p ClipOp) Add(o *ui.Ops) {
+func (p ClipOp) Add(o *op.Ops) {
 	data := make([]byte, opconst.TypeClipLen)
 	data[0] = byte(opconst.TypeClip)
 	bo := binary.LittleEndian
@@ -46,7 +46,7 @@ func (p ClipOp) Add(o *ui.Ops) {
 
 // Init the builder and specify the operations list for
 // storing the path data and final ClipOp.
-func (p *PathBuilder) Init(ops *ui.Ops) {
+func (p *PathBuilder) Init(ops *op.Ops) {
 	p.ops = ops
 }
 

text/editor.go

@@ -14,6 +14,7 @@ import (
 	"gioui.org/io/key"
 	"gioui.org/io/pointer"
 	"gioui.org/layout"
+	"gioui.org/op"
 	"gioui.org/paint"
 	"gioui.org/ui"
 
@@ -33,12 +34,12 @@ type Editor struct {
 	Submit bool
 
 	// Material for drawing the text.
-	Material ui.MacroOp
+	Material op.MacroOp
 	// Hint contains the text displayed to the user when the
 	// Editor is empty.
 	Hint string
 	// Mmaterial is used to draw the hint.
-	HintMaterial ui.MacroOp
+	HintMaterial op.MacroOp
 
 	oldScale          int
 	blinkStart        time.Time
@@ -218,7 +219,7 @@ func (e *Editor) Layout(gtx *layout.Context) {
 		Width:     e.viewWidth(),
 		Offset:    off,
 	}
-	var stack ui.StackOp
+	var stack op.StackOp
 	stack.Push(gtx.Ops)
 	// Apply material. Set a default color in case the material is empty.
 	if e.rr.len() > 0 {
@@ -233,9 +234,9 @@ func (e *Editor) Layout(gtx *layout.Context) {
 		if !ok {
 			break
 		}
-		var stack ui.StackOp
+		var stack op.StackOp
 		stack.Push(gtx.Ops)
-		ui.TransformOp{}.Offset(lineOff).Add(gtx.Ops)
+		op.TransformOp{}.Offset(lineOff).Add(gtx.Ops)
 		e.Face.Path(str).Add(gtx.Ops)
 		paint.PaintOp{Rect: toRectF(clip).Sub(lineOff)}.Add(gtx.Ops)
 		stack.Pop()
@@ -267,7 +268,7 @@ func (e *Editor) Layout(gtx *layout.Context) {
 			}
 		}
 		if blinking {
-			redraw := ui.InvalidateOp{At: nextBlink}
+			redraw := op.InvalidateOp{At: nextBlink}
 			redraw.Add(gtx.Ops)
 		}
 	}

text/label.go

@@ -8,9 +8,9 @@ import (
 	"image/color"
 	"unicode/utf8"
 
-	"gioui.org/ui"
 	"gioui.org/f32"
 	"gioui.org/layout"
+	"gioui.org/op"
 	"gioui.org/paint"
 
 	"golang.org/x/image/math/fixed"
@@ -22,7 +22,7 @@ type Label struct {
 	Face Face
 	// Material is a macro recording the material to draw the
 	// text. Use a ColorOp for colored text.
-	Material ui.MacroOp
+	Material op.MacroOp
 	// Alignment specify the text alignment.
 	Alignment Alignment
 	// Text is the string to draw.
@@ -118,9 +118,9 @@ func (l Label) Layout(gtx *layout.Context) {
 			break
 		}
 		lclip := toRectF(clip).Sub(off)
-		var stack ui.StackOp
+		var stack op.StackOp
 		stack.Push(gtx.Ops)
-		ui.TransformOp{}.Offset(off).Add(gtx.Ops)
+		op.TransformOp{}.Offset(off).Add(gtx.Ops)
 		l.Face.Path(str).Add(gtx.Ops)
 		// Set a default color in case the material is empty.
 		paint.ColorOp{Color: color.RGBA{A: 0xff}}.Add(gtx.Ops)

text/measure.go

@@ -6,8 +6,8 @@ import (
 	"fmt"
 	"image"
 
-	"gioui.org/ui"
 	"gioui.org/layout"
+	"gioui.org/op"
 	"golang.org/x/image/math/fixed"
 )
 
@@ -50,7 +50,7 @@ type Face interface {
 	// options.
 	Layout(s string, opts LayoutOptions) *Layout
 	// Path returns the ClipOp outline of a text recorded in a macro.
-	Path(s String) ui.MacroOp
+	Path(s String) op.MacroOp
 }
 
 type Alignment uint8

ui/doc.go

@@ -4,64 +4,6 @@
 Package ui defines operations buffers, units and common operations
 for GUI programs written with the Gio module.
 
-Operations
-
-Gio programs use operations, or ops, for describing their user
-interfaces. There are operations for drawing, defining input
-handlers, changing window properties as well as operations for
-controlling the execution of other operations.
-
-Ops represents a list of operations. The most important use
-for an Ops list is to describe a complete user interface update
-to a ui/app.Window's Update method.
-
-Drawing a colored square:
-
-	import "gioui.org/ui"
-	import "gioui.org/app"
-	import "gioui.org/paint"
-
-	var w app.Window
-	ops := new(ui.Ops)
-	...
-	ops.Reset()
-	paint.ColorOp{Color: ...}.Add(ops)
-	paint.PaintOp{Rect: ...}.Add(ops)
-	w.Update(ops)
-
-State
-
-An Ops list can be viewed as a very simple virtual machine: it has an implicit
-mutable state stack and execution flow can be controlled with macros.
-
-The StackOp saves the current state to the state stack and restores it later:
-
-	ops := new(ui.Ops)
-	var stack ui.StackOp
-	// Save the current state, in particular the transform.
-	stack.Push(ops)
-	// Apply a transform to subsequent operations.
-	ui.TransformOp{}.Offset(...).Add(ops)
-	...
-	// Restore the previous transform.
-	stack.Pop()
-
-The MacroOp records a list of operations to be executed later:
-
-	ops := new(ui.Ops)
-	var macro ui.MacroOp
-	macro.Record()
-	// Record operations by adding them.
-	ui.InvalidateOp{}.Add(ops)
-	...
-	macro.Stop()
-	...
-	// Execute the recorded operations.
-	macro.Add(ops)
-
-Note that operations added between Record and Stop are not executed until
-the macro is Added.
-
 Units
 
 A Value is a value with a Unit attached.

ui/ui.go

@@ -3,12 +3,7 @@
 package ui
 
 import (
-	"encoding/binary"
-	"math"
 	"time"
-
-	"gioui.org/f32"
-	"gioui.org/internal/opconst"
 )
 
 // Config define the essential properties of
@@ -19,60 +14,3 @@ type Config interface {
 	// Px converts a Value to pixels.
 	Px(v Value) int
 }
-
-// InvalidateOp requests a redraw at the given time. Use
-// the zero value to request an immediate redraw.
-type InvalidateOp struct {
-	At time.Time
-}
-
-// TransformOp applies a transform to the current transform.
-type TransformOp struct {
-	// TODO: general transformations.
-	offset f32.Point
-}
-
-func (r InvalidateOp) Add(o *Ops) {
-	data := make([]byte, opconst.TypeRedrawLen)
-	data[0] = byte(opconst.TypeInvalidate)
-	bo := binary.LittleEndian
-	// UnixNano cannot represent the zero time.
-	if t := r.At; !t.IsZero() {
-		nanos := t.UnixNano()
-		if nanos > 0 {
-			bo.PutUint64(data[1:], uint64(nanos))
-		}
-	}
-	o.Write(data)
-}
-
-// Offset the transformation.
-func (t TransformOp) Offset(o f32.Point) TransformOp {
-	return t.Multiply(TransformOp{o})
-}
-
-// Invert the transformation.
-func (t TransformOp) Invert() TransformOp {
-	return TransformOp{offset: t.offset.Mul(-1)}
-}
-
-// Transform a point.
-func (t TransformOp) Transform(p f32.Point) f32.Point {
-	return p.Add(t.offset)
-}
-
-// Multiply by a transformation.
-func (t TransformOp) Multiply(t2 TransformOp) TransformOp {
-	return TransformOp{
-		offset: t.offset.Add(t2.offset),
-	}
-}
-
-func (t TransformOp) Add(o *Ops) {
-	data := make([]byte, opconst.TypeTransformLen)
-	data[0] = byte(opconst.TypeTransform)
-	bo := binary.LittleEndian
-	bo.PutUint32(data[1:], math.Float32bits(t.offset.X))
-	bo.PutUint32(data[5:], math.Float32bits(t.offset.Y))
-	o.Write(data)
-}